Tank precharge pressure check valve

ABSTRACT

A check valve including a vertical column which is applied to the outlet of a pressure tank, a ball in the vertical column, and a separate smaller pipe e.g. a Venturi tube, which leads from the tank to the top of the column.

United States Patent Inventor Frederick G. ,I. Grise Ware Point Road,West Brookfield, Mas. 01506 App]. No. 784,029

Filed Dec. 16, 1968 Patented July 6, 1971 TANK PRECHARGE PRESSURE CHECKVALVE 1 Claim, 4 Drawing Figs.

U.S.Cl 137/192, 137/399, 251/24 lnt.C1 ..F16k 31/22, F16k 15/04 Field oiSearch 137/209- [56] References Cited UNlTED STATES PATENTS 1,646,64010/1927 Daniel 251/24 2,598,706 6/1952 Manning 137/192X 2,796,883 6/1957Thompson.. 137/399 3,097,604 7/1963 Morgan Primary Examiner-Robert G.Nilson Attorney-Charles R. Fay

ABSTRACT: A check valve including a vertical column which is applied tothe outlet of a pressure tank, a ball in the vertical column, and aseparate smaller pipe e.g. a Venturi tube, which leads from the tank tothe top of the column.

PATENTED JUL 6 I9?! &

IIIIIIIIIIIIIIIIIIIIIIIIIIIII Faaarzkk G- I Gnba TANK PRECIIARGEPRESSURE CHECK VALVE BACKGROUND OF THE INVENTION SUMMARY OF THEINVENTION In the present case a check valve associated with an outlet isapplied to a fluid tank below the normal fluid line. This valve isprovided with a vertical column containing fluid under normal conditionswith a ball floating therein, and a Venturi tube is located between thetop of the vertical column and the interior of the tank, so that whenthe water level drops to uncover the Venturi tube, the air pressure inthe tank passes through the tube into the column at. the top thereof,forcing the ball down into a position against a check valve seat,stopping flow from the tank and preventing any further drop of the fluidlevel and therefore of the pressure in the tank.

When the pump again starts to fill the tank, the ball is thereby floatedout of its checking position allowing water to flow past as before, Thisflow sucks air from the vertical column through the Venturi tubeallowing the ball and the water to rise in the column. Guideways areprovided to maintain the ball in the desired path between the column andthe check valve seat.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in elevation illustratingthe location of the new fixture or check valve;

FIG. 2 is a view in section on a larger scale illustrating theconstruction and operation of the device;

FIG. 3 is a view in elevation looking in the direction of arrow 3 inFIG. 2, and

FIG. 4 is a plan view.

PREFERRED EMBODIMENT OF THE INVENTION Referring now to FIG. 1, there isshown a conventional fluid tank 10. The normal fluid level is shown andabove the same in the chamber at 12 is air which provides pressure onthe fluid. A pump keeps the tank at this pressure regardless of thedemand, and a shutoff or check valve or the like is usually mounted inthe outgoing line, as well known.

The fixture shown in FIGS. 2 to 4 is provided with a threaded connection14 for securement with respect to the wall of the tank 10; and a doubleconnection for the pump and service at 16 and 18 in communication withthe tank and a vertical column 20, the column 20 being open with respectto the interior of the body of the device. A Venturi tube 22 has aninlet at 24 at connection 14 and it leads to the top of the verticalcolumn 20 as at 26. A lip at 28 enhances the Venturi effect.

This column will normally be filled with fluid approximately forinstance as shown or higher and a ball 30 floats in this area. The ballhas a nonnal position as shown in solid lines and an operative shutoffposition as shown in dotted lines in FIG. 2. There is also provided acurved guideway 32 which directs the ball between its floating positionin solid lines and its check position in dotted lines, against a seat 34particularly arranged for this purpose in the fixture.

In the operation of the device the ball will nonnally be in the solidline position in FIG. 2 and the fixture will be full of fluid whichpasses through the same upon demand. However if the pump should fail,the air pressure at 12 will continue to force fluid out of the tank inresponse to demand and in the prior art when the level reaches the levelof the fitting at 14 the air pressure will be lost and has to bereplaced upon resumption ration. owever in the present case the airpressure in the tank will travel through the Venturi tube 22 to the topof the vertical column and will press the ball down to a position whereit shuts off the flow as shown in dotted lines against seat 34, and thusthe air pressure will be maintained so that when the pump once morestarts up, it is not necessary to replenish the air pressure in the tankand the device will operate in a normal manner. 7

When the pump again starts to fill the tank, the flow is into the tank10. This flow sucks air down through the Venturi tube from the verticalcolumn allowing the ball and the water to rise in the column to originalposition. The ball is guided along the curved guideway 32 which isprovided with space to allow fluids to pass through.

Various gauges as at 36, clean out plugged holes etc. are available inthe fixture, and it is to be noted that all the parts except the ballcan be found unitarily in a single piece, preferably a casting.

Having thus described my invention and the advantages thereof, I do notwish to be limited to the details herein disclosed, otherwise than asset forth in the claims, but what I claim is:

l. A tank precharge check valve comprising a fixture attached to andhaving direct access to a tank normally maintained at a predeterminedpressure by means of a pump,

a column on said fixture open with respect thereto so that liquid islocated in the column, a check valve member floating in said column onsaid liquid, a check valve seat in said fixture opposite the connectionthereof to the tank and a venturi tube extending from the tank to theupper portion of said vertical column,

whereby under normal conditions the check valve member normally floatsin the column, but upon substantial depletion of liquid in the tank, airwill pass through the venturi tube into the column, forcing the checkvalve member down against said check valve seat, closing the demand lineand the air against escaping, wherein said venturi tube is constructedand arranged to provide for sucking air from the top of the verticalcolumn when liquid is supplied to the tank, allowing the check valvemember and the liquid to rise into the column upon restoration of normaloperation.

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1. A tank precharge check valve comprising a fixture attached to and having direct access to a tank normally maintained at a predetermined pressure by means of a pump, a column on said fixture open with respect thereto so that liquid is located in the column, a check valve member floating in said column on said liquid, a check valve seat in said fixture opposite the connection thereof to the tank, and a venturi tube extending from the tank to the upper portion of said vertical column, whereby under normal conditions the check valve member normally floats in the column, but upon substantial depletion of liquid in the tank, air will pass through the venturi tube into the column, forcing the check valve member down against said check valve seat, closing the demand line and the air against escaping, wherein said venturi tube is constructed and arranged to provide for sucking air from the top of the vertical column when liquid is supplied to the tank, allowing the check valve member and the liquid to rise into the column upon restoration of normal operation. 